And no one has mentioned CHOPPER. Feed 60cy into this coil and it will easily switch at that rate and much higher.
Give the man a prize!! It is a chopper relay!
I found it listed in a 1968 catalog from Electrosonic, a Canadian distributor. See, dead tree books do still have a use!
JM Series
JML sensitive, form C, non-bridging
CHOPPER
Capsule: JML
Coil: 8130
Terminal Figure #: 81 (just shows the same picture as the one on the relay).
Coil Characteristics
Resistance: 600 ohm +- 10%
Voltage RMS 60 Hz: 6.3V
The price was $15.45. I shudder to think what that would convert to in today's dollars.
Other relays in the JML series were shown as 'SINGLE SIDE STABLE' or 'BI-STABLE' instead of 'CHOPPER'. Does that mean that this relay isn't stable at all? Is it open on both sides and only makes contact when it's powered by AC? Don't know.
Descriptive info on the JM series is as follows:
Rare long life, high speed, and unvarying dependability - all are the result of the basic component of these relays: a hermetically sealed glass capsule. It contains the contact arrangement and a small reservoir of mercury sealed in a high pressure hydrogen atmosphere. A film of mercury is renewed for every operation - that's why you can think in terms of billions of operations without contact bounce, pits or welds.
TWO TYPES OF CAPSULES
The capsule used in JMF modules and JML relays has a SPDT, break-before-make (Form C), non-bridging contact arrangement. Each capsule used in JMP and JM1 to JM4 relays has a SPDT, make-before-break (Form D), bridging contact arrangement. JMF, JML and JMP series achieve a high rate of sensitivity by factory-adjusted magnet biasing.
CONTACT RATINGS
JML: 500V max., and 2 amps max., 100VA max.*
*With contact protection unless in a low level circuit. Details of a simple protection circuit consisting of resistor and capacitor in series are packed with each relay.
Ed